"That is the problem with us women: we follow our hearts," says screenwriter Tricia Walsh-Smith. "We're all into the love and happy-ever-after, and it's rubbish." As the wronged British socialite who famously took revenge on her husband by humiliating him on Youtube last year, it's easy to imagine why Walsh-Smith may not be love's greatest advocate. However, her bitter tale - a divorce that left her with a $45,000 credit card bill, huge legal costs and eviction from her apartment - is not so far removed from that of countless other women who have found themselves falling out of favour and out of pocket.

Heartbreak can be costly. A recent survey by Scottish Widows found that one in seven people in Britain would consider marrying purely for money, while the number of men making claims on their wives' wealth in divorce has doubled since last year. According to the Office of National Statistics, one in 10 marriages now end in divorce within five years, and wary women are drawing up contracts to ensure their assets are still alive and kicking long after the romance is dead.

"We're moving on as a society where women are a bit more realistic about relationships and whether or not they're going to endure," says Amandeep Gill, an associate of the law firm Davenport Lyons. "Times have changed. These days, you've got far more women in the workplace, they've generated wealth independently and, particularly if you've got a woman marrying later on in her thirties or forties, it's natural to want to protect one's wealth." In Walsh-Smith's case, the small print of her prenuptial agreement revealed clauses that served her husband's interests rather than hers, but a well-managed prenup can be invaluable.

A prenuptial agreement is a legal contract entered into prior to marriage and commonly includes provisions for how property and assets are to be divided, as well as spousal support, should the marriage break down and lead to divorce. Though prenups are not enforceable in England and Wales, they can be upheld at the judge's discretion and regularly act as an influential framework from which the courts can work, representing a barometer of understanding between the couple in happier times.

Prenups have become fixtures in high-profile marriages. In 2007, Paul McCartney's decision not to have a prenup with Heather Mills cost him £24.3m. In contrast, in the same year Britney Spears - worth an estimated $120m - gave a mere $1m to dancer Kevin Federline in their divorce after ensuring a watertight prenup. However, prenuptial agreements no longer simply protect multimillion-dollar fortunes and Malibu beach houses. These days, more and more Britons with less ostentatious incomes are proposing prenups before marriage.

Scottish Widows found that over half of people (56%) yet to be married would consider a prenuptial agreement. Of these, 12% saw a prenup as a way of securing financial independence, while 5% saw them as a way to ensure partners didn't get their hands on their money.

"There has certainly been a rise in enquiries in relation to prenups, and it's from people of all walks of life," says Gill. "I think the current economic climate is a big factor. Most people who have worked hard to achieve their wealth want to hang onto it and a prenup is de rigour these days." Prenups can especially appeal to young City entrepreneurs who have amassed independent wealth; professionals used to binding agreements in their working lives; and gay couples who have cohabited for years and are now entering civil partnerships.

Sandy Williams, 42, a businesswoman from London who has built up a property portfolio and two companies, is now in the process of drawing up a prenup for her second marriage. Her motivation is to protect her fiancé's interests as much as her own. "My partner's reaction to the idea of a prenup was positive as he knows that I am not planning to leave him with nothing, but rather the opposite. I'm planning for his future in the event of a break-up."

As unromantic the proposal might sound, Williams believes prenups are a basic financial decision. "It is 100% practical and it has nothing to do with love and romance. Prenups create more certainty and it will also protect us from each other's debts. I deeply love my partner and we are devoted to each other. I worked extremely hard for my money and my partner appreciates my intentions."

Forensic accountant Jeffrey Nedas agrees that some women would do well to consider a prenuptial agreement. "The advantage is that you are protecting your assets up front. The disadvantage is that you've got to tell your future husband what your assets are as you are going to have to disclose them. You might not want to do that but you can't have it both ways. Some people say that it might really upset your partner by telling him you want him to sign a prenup. To that I would say: it just proves that he's not just marrying you for your money."

To some women, though, the idea of planning the divorce before the marriage has even begun makes a mockery of the vow 'for richer, for poorer'. Mother of two Julie Spalding, 32, from Dorking, married banker David, 36, four years ago without a prenup. Even now, mid-recession, Julie doubts whether they would have proposed the idea. "I don't know if I would have signed it. The whole notion of marriage is that it's forever, so if I thought that David was thinking 'Well, if our marriage ends …' then that's quite sad really. I think I would have been disappointed and slightly offended."

Gill, however, believes prenups need not become a deal breaker. "The way to enter into these things is to negotiate it and have it signed off well in advance of the marriage, and let the prenup be a document that you hopefully put away in a drawer and forget about and let gather dust." Walsh-Smith has slightly more bullish advice for women banking on wedded bliss: "Totally protect your finances. Be absolutely as hard as nails with the prenup. See lawyers and if it's not right, do a reality check."

If a woman is considering a prenup in the first place, it suggests she has already had a reality check. After all, love may be blind, but that doesn't mean you can afford to wear rose-tinted glasses down the aisle.